package v1ch13.serviceLoader.impl;

import v1ch13.serviceLoader.*;

public class CaesarCipher implements Cipher {
	public byte[] encrypt(byte[] source, byte[] key) {
		byte[] result = new byte[source.length];
		for (int i = 0; i < source.length; i++)
			result[i] = (byte) (source[i] + key[0]);
		return result;
	}
	
	public byte[] decrypt(byte[] source, byte[] key) {
		return encrypt(source, new byte[]{(byte) -key[0]});
	}
	
	public int strength() {
		return 1;
	}
}